[1] Shaanxi Normal Univ, Key Lab Macromol Sci Shaanxi Prov, Shaanxi Key Lab Adv Energy Devices, Sch Mat Sci & Engn, Xian 710119, Shaanxi, Peoples R China
[2] Rhein Westfal TH Aachen, Mat Chem, D-52074 Aachen, Germany
[3] Forschungszentrum Julich, Ernst Ruska Ctr Microscopy & Spect Electrons, D-52425 Julich, Germany
[4] Forschungszentrum Julich, Peter Grunberg Inst, D-52425 Julich, Germany
[5] Rhein Westfal TH Aachen, Cent Facil Electron Microscopy, D-52074 Aachen, Germany